package com.heroCW.bodhiAttic.filter;

import com.alibaba.fastjson.JSON;
import com.heroCW.bodhiAttic.common.BaseContext;
import com.heroCW.bodhiAttic.resultUtil.Result;
import com.heroCW.bodhiAttic.resultUtil.ResultCode;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

/**
 * 检查用户是否已经完成登录
 */
@WebFilter(filterName = "LoginCheckFilter", urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {
    // 路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER = new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        HttpServletRequest request = (HttpServletRequest) servletRequest;
        HttpServletResponse response = (HttpServletResponse) servletResponse;


        // 获取本次请求的uri
        String requestURI = request.getRequestURI();
        log.info("拦截到请求,URI：{}", requestURI);

        // 不需要处理的请求路径
        String[] urls = new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login",
                "/user/logout",
        };

        // 移动端能接收到的URL
        String[] frontUrls = {
                "/shoppingCart/**",
                "/addressBook/**",
                "/order/userPage",
                "/order/submit",
                "/order/again",
                "/order/list",
                "/order/cancel",
                "/category/front/list",
                "/dish/front/list",
                "/setmeal/list",
                "/setmeal/dish/**",
                "/user/u**",
                "/user/all",
        };

        // 后台管理端能接收到的URL
        String[] backendUrls = {
                "/employee/page",
                "/category/page",
                "/dish/page",
                "/setmeal/page",
                "/order/page",
                "/user/page",
                "/category/backend/list",
                "/dish/backend/list",
                "/setmeal/status/**",
                "/dish/status/**",
                "/employee",
                "/category",
                "/dish",
                "/setmeal",
                "/order",
                "/user/status",
        };

        // 判断本次请求是否需要处理
        boolean check = check(urls, requestURI);
        boolean frontCheck = check(frontUrls, requestURI);
        boolean backendCheck = check(backendUrls, requestURI);

        // 如果不需要处理，则直接放行
        if (check) {
            log.info("本次请求{}不需要处理", requestURI);
            filterChain.doFilter(request, response);
            return;
        }

        if (request.getSession().getAttribute("user") == null && frontCheck) {
            log.info("前端用户未登录");
            response.getWriter().write(JSON.toJSONString(Result.error(ResultCode.USER_NOT_LOGIN_ERR, "NOT LOGIN")));
            return;
        }
        if (request.getSession().getAttribute("employee") == null && backendCheck) {
            log.info("后端用户未登录");
            response.getWriter().write(JSON.toJSONString(Result.error(ResultCode.USER_NOT_LOGIN_ERR, "NOT LOGIN")));
            return;
        }

        // 4.2 判断用户是否登录
        if (request.getSession().getAttribute("user") != null && frontCheck) {
            log.info("用户已登录，用户id为：{}", request.getSession().getAttribute("user"));
            Long userId = (Long) request.getSession().getAttribute("user");
            BaseContext.setCurrentId(userId);
            filterChain.doFilter(request, response);
            return;
        }

        // 4.1 判断登录状态，如果已登录，则直接放行
        if (request.getSession().getAttribute("employee") != null) {
            log.info("用户已登录，id为{}", request.getSession().getAttribute("employee"));
            //在这里获取一下线程id
            // long id = Thread.currentThread().getId();
            // log.info("doFilter的线程id为：{}", id);
            //根据session来获取之前我们存的id值
            Long empId = (Long) request.getSession().getAttribute("employee");
            //使用BaseContext封装id
            BaseContext.setCurrentId(empId);
            filterChain.doFilter(request, response);
            return;
        }


        //5.如果未登录则返回未登录结果,通过输出流方式向客户端页面响应数据
        log.info("用户未登录");
        response.getWriter().write(JSON.toJSONString(Result.error(ResultCode.USER_NOT_LOGIN_ERR, "NOT LOGIN")));
    }

    /**
     * 路径匹配，检查本次请求是否需要放行
     *
     * @param urls
     * @param requestURI
     * @return
     */
    public boolean check(String[] urls, String requestURI) {
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if (match) {
                return true;
            }
        }
        return false;
    }
}
